Becomes sluggish and wont change gears 2005 Hyundai Santa Fe 2.7L V6

Hyundai Sante Fe

Becomes sluggish and wont change gears

I will do my best to explain the issue. The car starts and drives, the issue started as a random occurrence and now happens all the time. While in N I can rev the engine and it hits about 4,000 RPM then cuts itself off back down to 2,500 RPM then revs back to 4,000 RPM. Now the main issue happens while driving. The car will accelerate right up to 3,000 RPM but then becomes sluggish and wont change gears. I can put it in manual and change gears at 3,000 RPM and the car will accelerate in 2nd gear back to 3,000 RPM and wont go past that. The Crank Shaft Sensor was replaced 2 years ago and I was attempting to replace the Throttle Position Sensor but its so old the screw basically melted as I twisted the screw driver once. Am I on the right path or am I just completely wrong with the TPS… Thanks for any help I get!

The action you described when in neutral is normal. The engine computer system has a built in rev limiter that will once the engine reaches 4,000 rpm cut it back down to 2,500 rpm. Again, this is normal. This is to prevent damage to the engine and allows the manufacturer to sleep at night while warranting your car.

As for the sluggish at around 3,000 rpm or not changing gears, that would be a different story. The sluggish part may be tune up related but the gear changing issue wouldn’t be. My first guess would be a failing VSS – Vehicle Speed Sensor.  Like I said, a guess. Proper diagnostics should take place. Connecting a scan tool and extracting the diagnostic trouble codes would be the best place to start. Post all codes found for further assistance.